WISE Catalog Just Got Wiser

The new AllWISE catalog will bring distant galaxies that were once invisible out of hiding, as illustrated in this image.  › Full image and caption

NASA's WISE mission has released a new and improved atlas and catalog brimming with data on three-quarters of a billion objects detected during two full scans of the sky.

WISE, which stands for Wide-field Infrared Survey Explorer, scanned the entire sky in infrared light in 2010, snapping a dozen pictures of every star and galaxy. By October of that year, the spacecraft ran out of the coolant needed to chill some of its heat-seeking detectors. NASA then decided to fund a second scan of the sky to look for asteroids and comets, in a project called NEOWISE.

But the images from that second sky scan were designed to catch moving asteroids, not stars and galaxies. Now NASA has funded a project called AllWISE to stack up all the WISE images, including those from the second sky scan, thereby doubling exposure times and making new stars and galaxies visible.

"By stacking up the data, we have created a monster database with dozens of individual measurements on every one of the infrared sources we detect," said Ned Wright of UCLA, the principal investigator of WISE.

One new feature of the enhanced WISE images is the ability to search for nearby stars, especially cooler ones that only show up in infrared light. Objects that are closer to us will appear to move across the sky over time in relation to background stars. This is the same reason why the planets march across our night skies while the stars seem to stay still. With the new atlas, astronomers can look at images of the sky taken six months apart; if something jumps across the images, then it must be located nearby and could be a never-before-seen neighbor.

The new catalog will also help with studies of distant galaxies, bringing those that were invisible to us before out of hiding.

"The extra depth of AllWISE lets us see galaxies so distant that their light was emitted in the first half of the history of the universe," said Peter Eisenhardt, the WISE project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

In addition to AllWISE, NASA decided to wake up the WISE spacecraft again to search for more asteroids (see http://www.jpl.nasa.gov/news/news.php?release=2013-257 ).

The technical details for accessing the AllWISE data are online at: http://wise2.ipac.caltech.edu/docs/release/allwise/ .

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages and operates the newly activated NEOWISE mission for NASA's Science Mission Directorate. The WISE mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA. More information is online at http://www.nasa.gov/wise and http://wise.astro.ucla.edu and http://www.jpl.nasa.gov/wise .

Whitney Clavin (818) 354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov

Little Telescope Spies Gigantic Galaxy Clusters

  

A galaxy cluster 7.7 billion light-years away has been discovered using infrared data from NASA's Wide-field Infrared Survey Explorer (WISE). Image credit: NASA/JPL-Caltech/UCLA/WIYN/Subaru.  Full image and caption

Our solar system, with its colorful collection of planets, asteroids and comets, is a fleck in the grander cosmos. Hundreds of billions of solar systems are thought to reside in our Milky Way galaxy, which is itself just a drop in a sea of galaxies.

The rarest and largest of galaxy groupings, called galaxy clusters, can be the hardest to find. That's where NASA's Wide-field Infrared Survey Explorer (WISE) can help. The mission's all-sky infrared maps have revealed one distant galaxy cluster and are expected to uncover thousands more.

These massive structures are collections of up to thousands of galaxies bound together by gravity. They were born out of seeds of matter formed in the very early universe, and grew rapidly by a process called inflation.

"One of the key questions in cosmology is how did the first bumps and wiggles in the distribution of matter in our universe rapidly evolve into the massive structures of galaxies we see today," said Anthony Gonzalez of University of Florida, Gainesville, who led the research program. The results are published in the Astrophysical Journal.

"By uncovering the most massive of galaxy clusters billions of light-years away with WISE, we can test theories of the universe's early inflation period."

WISE completed its all-sky survey in 2011, after surveying the entire sky twice at infrared wavelengths. The 16-inch (40-centimeter) telescope ran out of its coolant as expected in 2010, but went on to complete the second sky scan using two of its four infrared channels, which still functioned without coolant. At that time, the goal of the mission extension was to hunt for more near-Earth asteroids via a project called NEOWISE.

NASA has since funded the WISE team to combine all that data, allowing astronomers to study everything from nearby stars to distant galaxies. These next-generation all-sky images, part of a new project called "AllWISE," will be significantly more sensitive than those previously released, and will be publicly available in late 2013.

Gonzalez and his team plan to use the enhanced WISE data to hunt for more massive galaxy clusters. The first one they spotted, MOO J2342.0+1301, is located more than 7 billion light-years away, or halfway back to the time of the Big Bang. It is hundreds of times more massive than our Milky Way.

By scanning the whole sky with the improved AllWISE data, the team will sleuth out the true monsters of the bunch, clusters as big as thousands of times the mass of the Milky Way, assembled even earlier in the history of the universe.

Galaxy clusters from the first half of the universe are hard to find because they are so far away and because not very many had time to assemble by then. What's more, they are especially hard to see using visible-light telescopes: light that left these faraway structures in visible wavelengths has been stretched into longer, infrared wavelengths due to the expansion of space. WISE can hunt some of these rare colossal structures down because it scanned the whole sky in infrared light.

"I had pretty much written off using WISE to find distant galaxy clusters because we had to reduce the telescope diameter to only 16 inches [40 centimeters] to stay within our cost guidelines, so I am thrilled that we can find them after all," said Peter Eisenhardt, the WISE project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. and an author of the new paper. "The longer exposures from AllWISE open the door wide to see the most massive structures forming in the distant universe."

Other projects planned for the enhanced WISE data include the search for nearby, hidden cool stars, including those with masses as low as planets. If a large planet or tiny star does exist close to our solar system, an object some call "Tyche," then WISE's infrared data may reveal it.

Other authors of the new study are: Daniel Gettings and Conor Mancone of the University of Florida; Adam Stanford of Lawrence Livermore National Laboratory, Livermore, Calif., and University of California, Davis; Mark Brodwin of University of Missouri, Kansas City; Daniel Stern of JPL; Gregory Zeimann of University of California, Davis; Frank Masci of the Infrared Processing and Analysis Center at the California Institute of Technology, Pasadena; Casey Papovich of Texas A&M University, College Station; Ichi Tanaka of the National Astronomical Observatory of Japan; and Edward (Ned) Wright of UCLA.

JPL manages, and operated, WISE for NASA's Science Mission Directorate. Edward Wright is the principal investigator and is at UCLA. The mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA. More information is online at http://www.nasa.gov/wise , http://wise.astro.ucla.edu and http://www.jpl.nasa.gov/wise .

Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov